Subject: [PATCH 04/10] arm: zynq: Load scu baseaddress at run time

From: [email-masked] (Rob Herring)
Date: Mon, 25 Mar 2013 09:06:12 -0500

On 03/25/2013 08:53 AM, Michal Simek wrote:
> Use Cortex a9 cp15 to read scu baseaddress.
> 
> Signed-off-by: Michal Simek <[email-masked]>
> ---
>  arch/arm/boot/dts/zynq-7000.dtsi |    5 +++++
>  arch/arm/mach-zynq/common.c      |   33 +++++++++++++++++++++------------
>  arch/arm/mach-zynq/common.h      |    2 ++
>  3 files changed, 28 insertions(+), 12 deletions(-)
> 
> diff --git a/arch/arm/boot/dts/zynq-7000.dtsi b/arch/arm/boot/dts/zynq-7000.dtsi
> index 2a72339..4943568 100644
> --- a/arch/arm/boot/dts/zynq-7000.dtsi
> +++ b/arch/arm/boot/dts/zynq-7000.dtsi
> @@ -22,6 +22,11 @@
>  		interrupt-parent = <&intc>;
>  		ranges;
>  
> +		scu: scu at f8f000000 {
> +			compatible = "arm,cortex-a9-scu";
> +			reg = <0xf8f00000 0x58>;
> +		};
> +

It's fine to add this, but you don't really need it for this patch.

>  		intc: interrupt-controller at f8f01000 {
>  			compatible = "arm,cortex-a9-gic";
>  			#interrupt-cells = <3>;
> diff --git a/arch/arm/mach-zynq/common.c b/arch/arm/mach-zynq/common.c
> index 68e0907..13f9d8b 100644
> --- a/arch/arm/mach-zynq/common.c
> +++ b/arch/arm/mach-zynq/common.c
> @@ -33,10 +33,13 @@
>  #include <asm/mach-types.h>
>  #include <asm/page.h>
>  #include <asm/pgtable.h>
> +#include <asm/smp_scu.h>
>  #include <asm/hardware/cache-l2x0.h>
>  
>  #include "common.h"
>  
> +void __iomem *scu_base;
> +
>  static struct of_device_id zynq_of_bus_ids[] __initdata = {
>  	{ .compatible = "simple-bus", },
>  	{}
> @@ -56,17 +59,6 @@ static void __init xilinx_init_machine(void)
>  	of_platform_bus_probe(NULL, zynq_of_bus_ids, NULL);
>  }
>  
> -#define SCU_PERIPH_PHYS		0xF8F00000
> -#define SCU_PERIPH_SIZE		SZ_8K
> -#define SCU_PERIPH_VIRT		(VMALLOC_END - SCU_PERIPH_SIZE)
> -
> -static struct map_desc scu_desc __initdata = {
> -	.virtual	= SCU_PERIPH_VIRT,
> -	.pfn		= __phys_to_pfn(SCU_PERIPH_PHYS),
> -	.length		= SCU_PERIPH_SIZE,
> -	.type		= MT_DEVICE,
> -};
> -
>  static void __init xilinx_zynq_timer_init(void)
>  {
>  	struct device_node *np;
> @@ -81,13 +73,30 @@ static void __init xilinx_zynq_timer_init(void)
>  	clocksource_of_init();
>  }
>  
> +static struct map_desc zynq_cortex_a9_scu_map __initdata = {
> +	.length	= SZ_256,
> +	.type	= MT_DEVICE,
> +};
> +
> +static void __init scu_init(void)
> +{
> +	unsigned long base;
> +
> +	base = scu_a9_get_base();
> +	zynq_cortex_a9_scu_map.pfn = __phys_to_pfn(base);
> +	zynq_cortex_a9_scu_map.virtual = base;

You are setting the virtual address to the physical base?

> +	iotable_init(&zynq_cortex_a9_scu_map, 1);

Then creating a static mapping...

> +	scu_base = ioremap(base, zynq_cortex_a9_scu_map.length);

And also a dynamic mapping?

Rob